1. Field of Invention
The present invention relates to a circuit to drive a light source which includes a control device to drive the light source, which is composed of a discharge tube, and to switch the light source to a plurality of lighting modes including a rated power mode and a power saving mode. The invention also relates to a projector including the same; a method of controlling a light source which is executed in the circuit to drive the light source including the control device to drive the light source, which is composed of the discharge tube, and to switch the light source to the plurality of lighting modes including the rated power mode and the power saving mode; and to a program which executes the method of controlling the light source using the control device.
2. Description of Related Art
The related art includes projectors that can be used to modulate beams emitted from a light source according to image information, and to enlarge and project the modulated beams. The related art also includes projectors that can been used, for example, when a company makes presentations through a personal computer or a home user watches a movie.
In the company presentation, the light source needs to be lighted at high brightness, in order that every viewer can easily view the projected image. On the other hand, because the home user sees the image at a relatively short distance, the light source does not need to be lighted at high brightness.
Accordingly, a related art projector uses plural kinds of lighting modes including a rated power mode for presentations and a power saving mode for home theaters.
On the other hand, a related art high-pressure mercury lamp or related art metal halide lamp in which halogen gas is charged in a discharge tube can be employed as the light source for the projector to stably emit light at high brightness and stability (for example, see Japanese Unexamined Patent Application Publication No. 11-297268, and Japanese Unexamined Patent Application Publication No. 9-274886).